Hello everyone, I am encountering a confusing performance issue in VR when using Niagara particles or materials with any level of transparency.
Even in an almost empty scene (just a single sphere), the framerate may suddenly drop to 2 FPS.
However, this behavior is completely inconsistent: sometimes the project runs perfectly and I can spawn many effects without any lag.
In some cases, it will stutter heavily for about 20–30 seconds and then magically return to full framerate, but other times it never recovers.
Opaque and unlit materials always behave fine, which is why I initially suspected translucent rendering, but I can’t confirm this with certainty.
This is happening on a powerful PC with the latest version of UE5 and standard VR settings such as Forward Rendering / MSAA / Instanced Stereo enabled.
Restarting the engine or reloading the level can completely change performance from one iteration to the next.
Has anyone experienced this type of unstable VR rendering behavior, and is there a known setting or workaround that might explain it?
Thank you very much for any help